An alphavirus vector-based tetravalent dengue vaccine induces a rapid and protective immune response in macaques that differs qualitatively from immunity induced by live virus infection

J Virol. 2013 Mar;87(6):3409-24. doi: 10.1128/JVI.02298-12. Epub 2013 Jan 9.

Abstract

Despite many years of research, a dengue vaccine is not available, and the more advanced live attenuated vaccine candidate in clinical trials requires multiple immunizations with long interdose periods and provides low protective efficacy. Here, we report important contributions to the development of a second-generation dengue vaccine. First, we demonstrate that a nonpropagating vaccine vector based on Venezuelan equine encephalitis virus replicon particles (VRP) expressing two configurations of dengue virus E antigen (subviral particles [prME] and soluble E dimers [E85]) successfully immunized and protected macaques against dengue virus, while antivector antibodies did not interfere with a booster immunization. Second, compared to prME-VRP, E85-VRP induced neutralizing antibodies faster, to higher titers, and with improved protective efficacy. Third, this study is the first to map antigenic domains and specificities targeted by vaccination versus natural infection, revealing that, unlike prME-VRP and live virus, E85-VRP induced only serotype-specific antibodies, which predominantly targeted EDIII, suggesting a protective mechanism different from that induced by live virus and possibly live attenuated vaccines. Fourth, a tetravalent E85-VRP dengue vaccine induced a simultaneous and protective response to all 4 serotypes after 2 doses given 6 weeks apart. Balanced responses and protection in macaques provided further support for exploring the immunogenicity and safety of this vaccine candidate in humans.

Publication types

  • Research Support, N.I.H., Intramural

MeSH terms

  • Animals
  • Antibodies, Neutralizing / blood
  • Antibodies, Viral / blood
  • Cross Reactions
  • Dengue / prevention & control*
  • Dengue Vaccines / administration & dosage
  • Dengue Vaccines / genetics
  • Dengue Vaccines / immunology*
  • Disease Models, Animal
  • Drug Carriers*
  • Encephalitis Virus, Venezuelan Equine / genetics*
  • Genetic Vectors
  • Macaca
  • Vaccines, Synthetic / administration & dosage
  • Vaccines, Synthetic / genetics
  • Vaccines, Synthetic / immunology
  • Viremia / prevention & control

Substances

  • Antibodies, Neutralizing
  • Antibodies, Viral
  • Dengue Vaccines
  • Drug Carriers
  • Vaccines, Synthetic